MALE EFFECT: SUSTAINABILITY AND EFFECTIVENESS IN INDUCING ESTRUS IN GOATS/EFECTO MACHO: SOSTENIBILIDAD Y EFICIENCIA EN LA INDUCCIÓN DEL CELO EN CABRAS

The male effect is a strategy used in reproductive management of herds for the induction and synchronization of estrus, consisting of the reintroduction of males into a group of previously separated females. This interaction induces an increase in LH pulses followed by ovulation. In all species, there are communication mechanisms, many involving the use of chemoreceptor organs that enable the perception of pheromones, mediators in intraspecies interaction related to recognition for mating. Synchronization of female estrus by the male effect has many advantages reported by several authors, such as the reduction of costs, the absence of undesirable immune response by the use of chorionic gonadotropin, the decrease of hormonal residues in treated females, thus complying with ecological and sustainable production principles in animal production. El efecto macho es una estrategia usada en el manejo reproductivo de los rebaños para la inducción y sincronización del celo, consistiendo en la reintroducción de machos en un grupo de hembras previamente separadas. Esta interacción induce un incremento en los pulsos de LH seguidos por la ovulación. En todas las especies, existen unos mecanismos de comunicación, algunos involucran el uso de órganos quimiorreceptores que permiten la percepción de feromonas, mediadores en las interacciones intraespecíes relacionados con el reconocimiento para el apareamiento. La sincronización del celo en las hembras por el efecto macho tiene varias ventajas reportadas por diversos autores, tales como la reducción de costos, la ausencia de una respuesta inmune indeseada por el uso de gonadotropina coriónica, la disminución de residuos hormonales en las hembras tratadas, cumpliendo con los principios de una producción ecológica y sostenible en la producción animal.

Heat Stress and Body Temperature in Brown Swiss Cows Raised in Semi-Arid Climate of Ceará State, Brazil

Background: In tropical countries like Brazil, air temperature and relative humidity have a significant effect on animal physiology; there is a great impact of solar radiation on physiological parameters, especially on body temperature. This study evaluated the occurrence of heat stress in Brown Swiss cows in a tropical semi-arid climate, and checked for the correlation between internal body temperatures [rectal temperature (RT) and vaginal temperature (VT)] with surface temperature (ST) to determine if these variables are associated.Materials, Methods & Results: Twenty-eight Brown Swiss cows at three stages of the lactation cycle were used in this study: 10 nonpregant lactating (NPL) cows, 8 dry pregnant (DP) cows, and 10 pregnant lactating (PL) cows. These animals were between the second and third calving, weighed between 346 and 720 kg, and had ages between 2 and 13 years. During the experimental period, air temperature and relative humidity (RH) at the experimental site were measured using a digital thermohygrometer. The temperature and humidity index (THI) was calculated according to methodology described by Thom (1958), and was used as an environmental comfort parameter. For the evaluation of RT and VT, two digital clinical thermometers, one inserted in the vagina and the other in the rectum, were used simultaneously to minimize stress. Surface temperature (ST) was assessed using a digital infrared laser thermometer at a distance of 50 cm from the animal. Surface temperature was measured in the forehead (FST), thorax (TST), flank (FLST), and legs (LST). During the study period, the ambient temperature (AT) was significantly higher outside (in the sun) than inside of the facilities (in the shade) (P < 0.05). RH was inversely proportional to AT, and was significantly higher inside than outside the facilities (P < 0.05). Like AT, THI was significantly higher outside (in the sun) than inside the facilities (in the shade), with significant differences between these locations (P < 0.05). The amplitudes of the differences between the locations were as follows: 3.8°C for AT, 6.2% for RH, and 2.6 for THI. Mean values of rectal and vaginal temperatures were not significantly different from each other independent of lactation cycle stage, and were almost always significantly higher than the measured surface temperatures (P < 0.05). The maximum values obtained for each lactation cycle stage in this study were higher when compared to the mean values, showing that they are more representative of the occurrence of heat stress. Correlations between internal temperatures (RT and VT) and surface temperatures (TSF, TST, TSFL, and TSP) were weak and non-significant. ST values exhibited mostly weak, non-significant correlations, with the exception of FST with FLST and LST, which had moderate, significant correlations, as shown by the following coefficient factors: FST x FLST, 0.34; LST x FST, 0.415; and LST x FLST, 0.37.Discussion: A temperature of 34°C with RH ranging from 46% to 80% (i.e., a THI between 83 and 89) has been reported to have a significant thermal impact on dairy Brown Swiss cows; the THI values found in the present experiment were close to those. Body temperatures exhibited significant variations depending on the lactation cycle stage of the cows. Lactation concomitant with pregnancy significantly increases internal temperatures (RT and VT) in DP and NPL cows. This finding may be explained by the fact that pregnancy concomitant with lactation accelerates the metabolism, which results in higher food intake and increased production of body heat with consequent increase in internal body temperature. The maximum values of internal body temperatures (RT and TV) at all stages of the lactation cycle were higher than their corresponding average values, which indicates that some cows exhibited, at given moments, hyperthermia

TERMOGRAFIA INFRAVERMELHA APLICADA AO DIAGNÓSTICO DE MASTITE SUBCLÍNICA

Mastitis is an inflammatory disease of high incidence in dairy herds around the world, resulting in great economic losses in the milk production chain. There are several tests to detect the subclinical form of this disease, where the most applied are the somatic cell count (SCC) and the California Mastitis Test (CMT). However, due to their subjectivity, these tests can result in false-positive diagnoses. Therefore, new technologies have been studied for the early diagnosis of subclinical mastitis, including infrared thermography (IRT), which is a non-invasive diagnostic approach. Thus, this review aimed to discuss the infrared thermography technique and its applicability in the diagnosis of subclinical mastitis. The IRT has been successfully applied in numerous areas of precision animal production, including mastitis diagnosis, showing thermal alterations on the udder surface before the onset of clinical symptoms that are linked to milk SCC. Therefore, the use of this technology is a promising strategy to detect the unhealthy udder state, even in the subclinical form. However, further studies should be carried out to assess the applicability of this technique in commercial herds.A mastite é uma doença inflamatória de alta incidência nos rebanhos leiteiros de todo o mundo, sendo responsável por grandes prejuízos econômicos na cadeia produtiva do leite. Existem diversos testes para a detecção da forma subclínica da doença, sendo os mais utilizados: a contagem de células somáticas (CCS) e o California Mastitis Test (CMT). No entanto, esses testes possuem algumas limitações práticas, como a interpretação subjetiva, o que pode resultar em diagnósticos falso-positivos. Diante desses aspectos, novas tecnologias vêm sendo estudadas para auxiliar o diagnóstico precoce da mastite subclínica, dentre as quais a termografia infravermelha (TIV), que é um método não invasivo de diagnóstico por imagem. Dessa forma, o objetivo desta revisão foi discutir sobre a técnica de termografia infravermelha e sua aplicabilidade no diagnóstico de mastite subclínica. A TIV tem sido empregada, com sucesso, em várias áreas da produção animal de precisão, inclusive no diagnóstico de mastite, sendo relatadas alterações térmicas na superfície do úbere antes do aparecimento dos sintomas clínicos e sua correlação com a CCS do leite. O uso dessa tecnologia se mostra promissor para a detecção do estado não saudável do úbere, mesmo na forma subclínica. Entretanto, mais estudos devem ser realizados para que se avalie a aplicabilidade da técnica em rebanhos comerciais

Artificial insemination in dairy goats with estrus induced by male effect

Novas exigÃncias de mercado sÃo estabelecidas e com estas, novos modelos produtivos, com menor impacto ambiental, devem ser adotados para atender as necessidades dos consumidores, sem que resulte em prejuÃzos à produtividade do sistema. Assim, o objetivo deste estudo foi avaliar a eficiÃncia da bioestimulaÃÃo (Efeito Macho) pela taxa de concepÃÃo e pariÃÃo de cabras inseminadas artificialmente com sÃmen fresco. Para tanto, foram avaliadas a taxa de fertilidade e pariÃÃo de 73 cabras, pertencentes ao grupo genÃtico Saanen e seus mestiÃos com Anglonubiano, submetidas à inseminaÃÃo artificial, que tiveram o estro induzido e sincronizado pelo efeito macho. O experimento ocorreu durante os perÃodos chuvoso (marÃo-abril) e seco (agosto-setembro) de 2012. Foram coletados dados referentes Ãs variÃveis climÃticas (TA: temperatura ambiente; e UR: umidade relativa do ar) para o cÃlculo do ITU (Ãndice de temperatura e umidade). Os dados foram submetidos à anÃlise estatÃstica a 5% de probabilidade. O ITU foi mais elevado (P<0,05) para o perÃodo chuvoso, e assumiu valores acima dos ideais para caprinos, apresentando situaÃÃo de emergÃncia para o perÃodo chuvoso, e de perigo para o perÃodo seco. O efeito macho mostrou-se eficiente independente da Ãpoca do ano, resultando em 94,5% cabras em estro. A duraÃÃo do primeiro estro foi semelhante entre o perÃodo chuvoso e seco, com mÃdia geral de 23,4 horas. O intervalo entre inÃcio do efeito macho e manifestaÃÃo do estro de 11 dias, havendo uma maior manifestaÃÃo de estro (primeiro estro) logo na primeira semana para ambos os perÃodos. Em geral, 65% das cabras retornaram em estro, sendo o intervalo entre o inÃcio do efeito macho e a manifestaÃÃo do segundo estro foi maior (P<0,05) para o perÃodo chuvoso (27,8 dias), isto està relacionado ao tipo de ciclo estral, onde houve um maior (P<0,05) nÃmero de ciclos normais (20) para este perÃodo, e um elevado (P<0,05) nÃmero de ciclos curtos (15) para o perÃodo seco. A fertilidade para o perÃodo seco (57,6%) foi proporcionalmente superior ao perÃodo chuvoso (44,4%). No entanto, a taxa de pariÃÃo mostrou uma tendÃncia (P=0,57) a ser superior para o perÃodo seco. Esta menor taxa para o perÃodo chuvoso pode estar relacionado à alta variaÃÃo climÃtica observada durante o perÃodo experimental. Em geral, o segundo estro foi mais propÃcio à resultar em fertilidade, seja para o perÃodo chuvoso ou seco. Com isso, conclui-se que a inseminaÃÃo artificial de cabras com estro induzido e sincronizado pelo uso do efeito macho à um manejo que pode ser empregado para a produÃÃo de caprinos resultando em Ãndices reprodutivos satisfatÃrios.New market requirements are established and with them, new production models it should be adopted to meet the consumers demands, without resulting in damage to system productivity, with less environmental impact. The aim this study was to evaluate the effectiveness of Male Effect by fertility rate of goats inseminated artificially. Thus, we evaluated the fertility and calving rates of 73 goats belonging to genetic group Saanen and its crossbred. This does had their estrus induced and synchronized by the male effect and it were artificially inseminated with fresh semen. The experiment took place during the rainy (March-April) and dry (August-September) seasons of 2012. We collected data on climatic variables (RT: room temperature; and RH: relative humidity) for calculating the THI (temperature and humidity index). Data were analyzed statistically at 5% probability. The THI was higher (P<0.05) in the rainy season, and it assumed values above ideal for goats, with an emergency situation to the rainy season, and dangerous situation to the dry season. The male effect was effective regardless of season, it resulting in 94.5% of estrus. The duration of the first estrus was same between the rainy and dry season, it had a mean duration of 23.4 hours. The interval between the onset of the male effect and estrus was 11 days, and there was a greater manifestation of estrus (first heat) in the first week for both seasons. Overall, 65 % of goats returned in estrus, it been the interval between the onset of the male effect and second estrus manifestation was greater (P<0.05) during the rainy season (27.8 days). This is related to the estrous cycle length, where there was a greater (P <0.05) number of normal estrus cycles (20) during rainy season, and high (P <0.05) number of short estrus cycles (15) during dry season. The fertility during the dry season (57.6 %) was proportionally greater than rainy season (44.4 %). However, the calving rate showed a trend (P = 0.57) to be higher the dry season. This lower rate during rainy season may be related to high climate variability observed during this experimental period. The second estrus was more like to result in fertility, during rainy or dry season. This indicates that the artificial insemination of goats with induced and synchronized estrus by male effect is a management can be utilized in goat production systems resulting in satisfactory reproductive rates

BIOESTIMULAÇÃO PELO EFEITO MACHO

The male effect is a sitnple technique which aims the induction of estrus and ovulation, which is the reintroduction of male to a female group previously separated. This interaction leads to an increase in LH pulse followed by ovulation. One of the strategies for estrus induction is exposure of females to males. ln all species there are communication strategies, many of them involving the use of chemoreceptor organs that enable the perception of pheromones , and these mediators in the interaction intra species related to recognition for mating. The syncluonization of estrus by the male effect is an important step in the reproductive manageme.nt of herds, since the advantages indicated by severa! authors reflect directly on reducing costs, avoid undesirable immune response by the use of choionic gonadotropin , decreases hormone residues in treated females thus complying with ecological principles and sustainable production.O efoito macho é uma técnica simples que objetiva a indução do estro e da ovulação, e consiste na reintrodução de machos a um grupo de fêmeas previamente separadas. Esta interação induz a um aumento dos pulsos de LH seguido da ovulação. Uma das estratégias para indução do estro é a exposição das fêmeas a machos. Em todas as espécies existem estratégias de comunicação, muitas delas envolvendo o uso de órgãos quimiorreceptores que possibilitam a percepção de feromônios, sendo estes mediadores na interação entre a espécie relacionada ao reconhecimento para o acasalamento. A sincronização do estro de fêmeas pelo efeito macho constitui importante medida no manejo reprodutivo de rebanhos , uma vez que as vantagens indicadas por diversos autores retletem diretamente na redução de custos, evita resposta imunológica indesejável pelo uso das gonadotrofinas crônicas, diminui resíduos hormonais nas fêmeas tratadas, cumprindo assim com preceitos ecológicos e de produção sustentável

Efeito da administração de Flunixina Meglumine sobre as características seminais de machos ovinos e caprinos

Testicular degeneration is a multifactorial process increasing the concentration of prostaglandins in seminal plasma. Both increase and decrease of these hormones tend to promote loss of seminal quality. Flunixin meglumine is a potent anti-inflammatory drug capable of modulating the production of prostaglandins and is widely used in female reproduction. However, it is rarely used in males with the same objective. Therefore, this study aimed to evaluate the effects of this drug on seminal quality of male lambs and goats with spermatic characteristics unfavorable for reproduction. To this end, a total of 15 breeding animals were evaluated, of which six goats and four sheep with poor seminal quality were selected according to the criteria established by the Brazilian College of Animal Reproduction (CBRA). Three semen samples were collected from each animal. Then, the flunixin meglumine treatment was initiated and ejaculates were collected at two different periods after the drug was administered (from day 21 until day 35 and from day 49 to day 63). Macroscopic and microscopic parameters were assessed in semen samples and scrotal circumference and percentages of sperm pathologies were measured and compared between the three periods. Data with normal distribution were analyzed using ANOVA at 5% probability, and comparisons between periods within the same species were performed using the Tukey test. An improvement was observed in the analyses of mass motility, percentage motility, and sperm vigor. Scrotal circumference had no variation. Concerning sperm pathologies, an increase in the number of normal spermatozoids was observed due to a significant reduction in minor and major defects, and the latter remained low even after the treatment was finished. Therefore, flunixin meglumine presented beneficial effects on seminal parameters of male goats and lamb with unfavorable spermatic characteristics. These findings indicate this drug may be used in the treating of males with testicular injuries or of breeders with reduced seminal quality due to advanced age.A degeneração testicular é um processo multifatorial que leva ao aumento das prostaglandinas no plasma do ejaculado, sendo que tanto seu acréscimo quanto a redução baixam a qualidade seminal. A Flunixina Meglumine é um potente anti-inflamatório, capaz de modular a produção de prostaglandinas, amplamente difundido na reprodução de fêmeas, mas pouco utilizado em machos para esse fim. Por isso, esse trabalho buscou avaliar o efeito deste fármaco sobre a qualidade seminal de machos ovinos e caprinos que apresentem quadro espermático desfavorável à reprodução. Para tanto, um total de 15 reprodutores pertencentes à Universidade Federal do Ceará foram avaliados, dos quais foram selecionados seis bodes e quatro carneiros com sêmen de baixa qualidade, segundo os critérios do Colégio Brasileiro de Reprodução Animal (CBRA). Foram realizadas três colheitas prévias de cada animal, aplicado o tratamento com Flunixina Meglumine e, em seguida, foram colhidos ejaculados de dois momentos posteriores à aplicação do fármaco (do D21 ao D35 e do D49 ao D63). Os parâmetros espermáticos de natureza macro e microscópica, assim como a circunferência escrotal e o percentual de patologias espermáticas foram comparados entre os três momentos e os dados de distribuição normal foram avaliados por ANOVA a 5% de probabilidade e as comparações entre os momentos dentro de cada espécie quando significativa foram feitas pelo teste de Tukey. Houve melhora na motilidade massal, motilidade percentual e vigor espermático. Não ocorreu variação da circunferência escrotal e, no tocante às patologias espermáticas, observou-se um aumento no número de espermatozoides normais, devido a uma redução significativa de defeitos menores e maiores, sendo que estes permaneceram menores mesmo após cessar a influência do tratamento. Assim, a Flunixina Meglumine mostrou uma ação benéfica sobre os parâmetros seminais de machos ovinos e caprinos com quadro espermático desfavorável, sugerindo a indicação do fármaco para o tratamento de machos que passaram por injúrias testiculares diversas ou reprodutores com declínio da qualidade seminal devido à idade avançada

Desempenho reprodutivo de cabras leiteiras submetidas à indução e sincronização do estro com o uso de dispositivos de progesterona reutilizados

O estudo avaliou a manifestação de estro, taxa de prenhez e parição em cabras leiteiras utilizando um dispositivo intravaginal a base de progesterona natural (CIDR®) após duas e três utilizações. Para tanto, foram utilizadas cabras nulíparas e pluríparas divididas em dois grupos experimentais de sincronização de estro, CIDR® reutilizado 01 vez (n=37) e CIDR® reutilizado 02 vezes (n=28). As fêmeas de todos os grupos receberam o mesmo tratamento hormonal com o emprego do dispositivo vaginal por cinco dias associado à aplicação intramuscular de um análogo de prostaglandina F2α (75µg) e a bioestimulação pelo efeito macho na retirada dos dispositivos. O intervalo entre a retirada do dispositivo e o início do estro foi de 31,06 ± 11,27 h para as nulíparas e de 61,05 ± 19,53 h para as pluríparas do grupo CIDR® reutilizado uma vez (P<0,05). A taxa de prenhez foi de 76,5% e 68,7% para as nulíparas e pluríparas, respectivamente, enquanto que, a taxa de parição foi de 100% para as nulíparas e de 72,7% nas pluríparas (P<0,05). Para o grupo CIDR® reutilizado duas vezes, o intervalo entre a retirada do dispositivo e o início do estro foi de 52,21 ± 22,41 h para as nulíparas e de 52,36 ± 14,47 h para as pluríparas (P<0,05). A taxa de prenhez foi de 78,58% e 90,90% para as nulíparas e pluríparas, respectivamente; a taxa de parição foi de 81,81% para as nulíparas e de 100% nas pluríparas (P<0,05). Assim, o dispositivo CIDR® permite ser reutilizado até três vezes em protocolo de curta duração (cinco dias) associado a um análogo de prostaglandina e ao efeito macho na sincronização e/ou indução de estro para cabras leiteiras sem prejuízos nos índices de manifestação de estro.   Palavras-chave: estro, sincronização, CIDR®, cabras leiteira

Heat Stress and Body Temperature in Brown Swiss Cows Raised in Semi-Arid Climate of Ceará State, Brazil

Background: In tropical countries like Brazil, air temperature and relative humidity have a significant effect on animal physiology; there is a great impact of solar radiation on physiological parameters, especially on body temperature. This study evaluated the occurrence of heat stress in Brown Swiss cows in a tropical semi-arid climate, and checked for the correlation between internal body temperatures [rectal temperature (RT) and vaginal temperature (VT)] with surface temperature (ST) to determine if these variables are associated.Materials, Methods &amp; Results: Twenty-eight Brown Swiss cows at three stages of the lactation cycle were used in this study: 10 nonpregant lactating (NPL) cows, 8 dry pregnant (DP) cows, and 10 pregnant lactating (PL) cows. These animals were between the second and third calving, weighed between 346 and 720 kg, and had ages between 2 and 13 years. During the experimental period, air temperature and relative humidity (RH) at the experimental site were measured using a digital thermohygrometer. The temperature and humidity index (THI) was calculated according to methodology described by Thom (1958), and was used as an environmental comfort parameter. For the evaluation of RT and VT, two digital clinical thermometers, one inserted in the vagina and the other in the rectum, were used simultaneously to minimize stress. Surface temperature (ST) was assessed using a digital infrared laser thermometer at a distance of 50 cm from the animal. Surface temperature was measured in the forehead (FST), thorax (TST), flank (FLST), and legs (LST). During the study period, the ambient temperature (AT) was significantly higher outside (in the sun) than inside of the facilities (in the shade) (P &lt; 0.05). RH was inversely proportional to AT, and was significantly higher inside than outside the facilities (P &lt; 0.05). Like AT, THI was significantly higher outside (in the sun) than inside the facilities (in the shade), with significant differences between these locations (P &lt; 0.05). The amplitudes of the differences between the locations were as follows: 3.8°C for AT, 6.2% for RH, and 2.6 for THI. Mean values of rectal and vaginal temperatures were not significantly different from each other independent of lactation cycle stage, and were almost always significantly higher than the measured surface temperatures (P &lt; 0.05). The maximum values obtained for each lactation cycle stage in this study were higher when compared to the mean values, showing that they are more representative of the occurrence of heat stress. Correlations between internal temperatures (RT and VT) and surface temperatures (TSF, TST, TSFL, and TSP) were weak and non-significant. ST values exhibited mostly weak, non-significant correlations, with the exception of FST with FLST and LST, which had moderate, significant correlations, as shown by the following coefficient factors: FST x FLST, 0.34; LST x FST, 0.415; and LST x FLST, 0.37.Discussion: A temperature of 34°C with RH ranging from 46% to 80% (i.e., a THI between 83 and 89) has been reported to have a significant thermal impact on dairy Brown Swiss cows; the THI values found in the present experiment were close to those. Body temperatures exhibited significant variations depending on the lactation cycle stage of the cows. Lactation concomitant with pregnancy significantly increases internal temperatures (RT and VT) in DP and NPL cows. This finding may be explained by the fact that pregnancy concomitant with lactation accelerates the metabolism, which results in higher food intake and increased production of body heat with consequent increase in internal body temperature. The maximum values of internal body temperatures (RT and TV) at all stages of the lactation cycle were higher than their corresponding average values, which indicates that some cows exhibited, at given moments, hyperthermia